Traditional facial masks used for medical situations range from basic cloth patches that cover the mouth and nose, to more elaborate formed structures that have fibrous structures that create a filter effect for air that is breathed in by the user as well as exhaled by the user. In some cases, the filter effect is directed at protecting the user from inhaled pathogens or contaminants, and in some cases the intent is to prevent the user from exhaling pathogens or infections particles. In general, most commercially available respirators are intended for a one time use and discarded. They are difficult or expensive to sterilize and return to as new condition. In addition, most if not all commercially available respirators are designed and used to reduce exposure to pathogens and do not attack the potential pathogens themselves.
Embodiments described herein provide for a facepiece with a main body having a geometry configured to fit on a human face and cover the human's mouth and nose. The main body defines an interior cavity between the main body and the human's face. One or more straps extend from the main body and are configured to extend around the ears or head of a human such that the main body is held on the human's face. The facepiece includes one or more baffles disposed on the main body and in an airflow path between the interior cavity and an external environment. The one or more baffles have a first surface disposed to deflect air traveling along the airflow path. The first surface has a metal layer exposed to air traveling along the airflow path.
Understanding that the drawings depict only exemplary embodiments and are not therefore to be considered limiting in scope, the exemplary embodiments will be described with additional specificity and detail through the use of the accompanying drawings, in which:
Facepiece 100 includes a main body 102 having or more straps 104 extending therefrom. The main body 102 defines an interior cavity 106 and is configured to cover a mouth and a nose of a user. In this example, the main body 102 is sufficiently rigid to maintain its overall shape during normal care on and off of a user's face. Example materials that are sufficiently rigid include melt blown GSM materials used in conventional facial masks and respirators, polymers, including thermoelastic polymers such as liquid crystal polymer (LCP), polyimide, polyolefin, Polycarbonate, PEI, Acrylic, Silicone, Neoprene, and others. Liquid Crystal Polymer (LCP) is a thermoplastic material that can be shaped, formed, and molded. LCP is impervious to moisture and is biocompatible. In still other examples, an insufficiently rigid material (e.g., cloth fabric) can be used along with a rigid frame to provide an overall rigid geometry for the body 102. The interior cavity 106 is sized such that the user's nose and mouth fit within the cavity 106. In this example, the main body 102 has a generally concave geometry defining a single depression large enough to cover both the user's nose and mouth. In other examples, other geometries can be used.
In one example, main body 102 has a construction based upon Polycarbonate or Acrylic polymers that provide mechanical infrastructure to incorporate multiple components and features while being optically clear to allow for the users face and facial expressions to be viewed while conventional respirators block the view of the face. These polymers will typically yield a rigid structure but depending on the design the facepiece 100 could be made flexible or partially flexible for reasons such as flat storage or distribution.
The general shape and appearance of the main body 102 and overall respirator can be generally curvilinear and in basic terms serves as the structure that holds and presents the filtration and anti-pathogen structure at the proper location within the airflow path. The structure also serves as the skeleton for arranging and attaching various components that provide features such as facial sealing, respirator retention on the user's head, filter replacement, electronics integration, filter attachment etc.
In still other examples, the main body 102 can be flexible in nature, such that main body 102 has no rigid three-dimensional shape. In such examples, the main body 102 takes a generally concave geometry that covers the user's nose and mouth upon being strapped to the user's face. An example of such a flexible material is a cloth fabric, for example, composed of cotton, nylon, wool, silk, or a combination thereof.
The one or more straps 104 are configured to hold the facepiece 100 onto the face of the user. In this example, the one or more straps 104 are configured to wrap around the ears of the user, but other straps can be used such as one or more straps extending around the back and/or top of the user's head. In use, the facepiece 100 is configured to be placed over the mouth and nose of a user such that the outer rim 108 of the main body 102 contacts the user's face around the mouth and nose.
The facepiece 100 provides one or more airflow paths for air to flow between the interior cavity 106 and the external environment while the facepiece 100 is being worn. Accordingly, the airflow paths provide a path for a user's breath to enter and/or exit the interior cavity 106 as the user inhales and/or exhales while wearing the facepiece 100. In some examples, the main body 102 is composed of materials that provide airflow paths across the entirety of the main body 102, such as is the case with cloth fabric or melt blown GSM material. In other examples, the main body 102 is composed of materials, such as a thermoelastic polymer, that blocks airflow between the interior cavity 106 and the external environment. In such other examples, the main body 102 defines one or more passages through the impervious material, wherein the passages which provide airflow paths from the interior cavity 106 to the external environment.
The facepiece 100 also includes one or more antipathogen baffles on the main body 102. The baffle(s) are disposed in an airflow path of the main body 102 and positioned to deflect the air traveling along the airflow path. The baffles have one or more antipathogen materials thereon that are configured to interact with the air as it travels along the airflow path. In an example, one or more anti-pathogen materials are disposed on one or more surfaces on which the air traveling along the airflow path is incident. Thus, air traveling along the airflow path is forced into contact with the anti-pathogen material. The antipathogen material can then act to disable viruses and bacteria in the air as it travels between the interior cavity 106 and the external environment. In an example, the antipathogen material includes a metal layer that is exposed to the air on the surface of the baffle. In an example, the metal layer includes one or more metals and/or metal oxides selected from the group consisting of copper, silver, zinc, nickel, copper oxide, silver oxide, and zinc oxide. In such an example, the baffle can be composed of solid metal (e.g., copper) or can be composed of a substrate (e.g., LCP) having a metal layer on one or both sides thereof. In some examples, the antipathogen layer can be composed solely of a metal such as copper, silver, or zinc (e.g., at least 90%, 96%, or 99.9% pure copper, silver, and/or zinc). The exposed metal layer can be, but need not be, visibly exposed. That is, the metal layer can be covered with one or more layers of material that allows the air in the airflow path to travel through the material and contact the metal layer on its way through the main body 102 of the facepiece 100.
The main body 102 and the baffles are configured such that the air is directed against the exposed antipathogen material as the air travels into and/or out of the airflow path. Directing the air flow against the exposed antipathogen material can cause pathogens into the air flow to contact the antipathogen material, which will then disable the pathogens, such that they are destroyed or otherwise rendered inactive. As used herein an antipathogen material is a material that is effective at disabling, killing, and/or destroying viruses and microbes, such as bacteria and other microorganisms. In this way, the facepiece 100 is configured to direct the air flow between the interior cavity 106 and the external environment, such that the air comes into contact with exposed antipathogen material as it is flowing through the passages, thereby disabling pathogens in that air.
In an example, the airflow paths through the main body 102 can be sufficiently tortuous and small that pathogens are also captured (filtered out) as the air passes through the main body 102. For example, the airflow paths can capture sufficient pathogens that the facepiece 100 meets the N95 standard for respirators in the United States of America.
In an example, the baffle(s) in the main body 102 are rigid such that they are not significantly bendable by hand (e.g., more than 10 degrees). In another example, the baffle(s) are bendable by hand (e.g., more then 10 degrees), but have an elastic memory such that the baffle(s) maintain their shape absent forces bending the baffle.
In the example shown in
The baffle 400 also defines a plurality of smaller flaps 404. In this example, the smaller flaps 404 are defined within the larger flaps 402. The smaller flaps 404 are configured to be smaller than the apertures defined between the spokes 604 of the pinwheel spacer 506 such that the smaller flaps 404 when positioned appropriately do not contact the spokes 604 or the outer ring 602 of the pinwheel spacer 506. This allows the smaller flaps 404 to flex towards the pinwheel spacer. In this way, the larger flaps 402 are configured to flex one direction (e.g., outward) and the smaller flaps 404 are configured to flex in the other direction (e.g., inward). Advantageously, by embedding the smaller flaps 404 in the larger flaps 404, the surface area of surface area of the baffle 400 is well utilized. This is because air is forced against a large portion of the first side of the baffle 400 when the larger flaps 402 flex in the first direction. Additionally, air is forced past a large portion of the second side of the baffle 400, reverse of the first side, when the smaller flaps 404 flex in the second direction. The baffle 400 has an antipathogen layer on both sides and acts a pseudo exhaust valve along with the filter.
In an example, the fine mesh layers 503, 507, 508 are a thin cotton layer to contain any filter layer fibers and provide a clean outer surface. In an example, the filter layer 502 is a cotton batting filter layer or alternate N95 type spun polyester non-woven filter material. In an example, the fine mesh layer 503 between the ring spacer 506 and the filter layer 504 keeps the material of the filter layer 502 spaced from the baffle 400 to allow space for the flaps 402, 404 of the baffle 400 to flex. In an example, the baffle 400 is composed of a polymer, such as Kapton, polyester, polyolefin, LC with copper on both sides. In an example, the slots defining the flaps 402, 404 in the baffle 400 are 1 mm across. In an example, the pinwheel spacer layer 506 allows the major (larger) flaps 402 of the baffle 400 to flex outward during exhale and allows the interior (smaller) arrowhead shaped flex flaps 404 to flex inward during inhale. The pinwheel spacer 506 can be a molded part to provide contour support and keep the filter layer 502 from bunching or trying to impede the flex features from moving. In an example, the fine mesh layer 508 on the outside of the pinwheel spacer 506 can enclose the baffle 400.
As described above, the major flex flaps 402 of the baffle 400 reside on the webs of the pinwheel spacer 506 which will prevent inward flexure during inhale, while the spacer ring 504 provides space for the major flaps 402 to flex during exhale. The interior flex flaps 404 can flex inward during inhale and will likely be subordinate during exhale. In an example, the airstream flow through the filter layer 502 during inhale and exhale while driving the airflow in contact with the exposed antipathogen layers on the baffle 400 as much as possible without restricting too much airflow without large perforations. Although only a single baffle 400 is shown, in other example, multiple baffles and corresponding ring spacers, pinwheel spacers, are disposed Another copper circuit layer (e.g., copper flex layer 3308) can be added to increase the anti-pathogen effect. Although a specific geometry for the flaps 402, 404 of the baffle 400 is shown and described, other geometries having flexible flaps can be used.
In some examples, there are no additional materials in the recesses 1102, such that the inside surfaces of the recesses 1102 are the same material as the rest of the antipathogen surface of the baffle 1100. In the example shown in
Any of the baffles described herein can be planar (i.e., flat) or can have a three-dimensional geometry (e.g., a concave or convex shape). In an example, the substrate of the baffle is a polymer layer formed by extrusion and is initially flat. In an example, the polymer layer substrate is initially between 1 and 1000 microns thick and can have any suitable length and width. The polymer layer can then be plated, using circuit board fabrication techniques, with an antiviral material, such as silver or copper. The metal bearing film can be subject to etching and deposition techniques to form the recesses and/or rises on the antipathogen surface. The metal bearing film can also be die cut or otherwise processed to create any flaps or apertures therein. After extrusion and formation of the antipathogen layers and any recesses, rises, flaps, or apertures, the fabricated substrate can be subject to thereto-elastic processing to form the flat sheet into a three-dimensional shape as desired.
Any of the features described herein can be mix and matched, with the basic principle of cutting slits or material separations that allow for air flow but reduce the effective gap to provide contact to the antiviral material exposed on the surface. The net airflow effect can be set by adjusting the pattern and/or size of slits, flaps, or apertures. The LCP can also be treated with a plasma deposited monomer to create anti-wetting characteristics where desired, as well as microfluidic channels can be added to control and direct fluid or moisture accumulation.
Any of the baffles herein can be formed in a polymer material that is contiguous with the main body 102 or can be formed in a cartridge that is removably secured to the main body 102.
The antipathogen baffle placed within the airflow path in some fashion has significant advantages over the methods used to incorporate particles, threads, or coatings within a facepiece. Those methods have a relatively small density of anti-microbial or antiviral material relative to the actual material content of the mask and corresponding airflow volume. In other words, the vast majority of the airflow and airborne pathogens pass through the untreated areas of the fabric. The use of a surface bearing anti-pathogen properties significantly increases the probability of any airborne pathogen encountering the surface and remaining in a disabled state no longer able to infect or replicate. Since the airborne pathogen are essentially caried by moisture droplets large and small, the surface can be enhanced to promote pathogen capture and prolong the duration of direct contact with the anti-pathogen measures.
This application claims the benefit of U.S. Provisional Application No. 63/142,422, filed on Jan. 27, 2021, entitled “PLANAR ANTI-PATHOGEN STRUCTURE SUSPENDED WITHIN THE AIR FLOW PATH WITHIN A PROTECTIVE FACIAL MASK OR RESPIRATOR”, which is hereby incorporated herein by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2022/014018 | 1/27/2022 | WO |
Number | Date | Country | |
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63142422 | Jan 2021 | US |